I've used Tubscreamers to push Marahalls for years, with sc and hb p'ups. I like a Boss SD-1 a little better but honestly it's not a drastic difference.

Personally I hate the tube screamer anyway. I’d rather be using a Boss Blues Driver, But that’s the low cost option. The new Highway 41 from @mlapedals1 audio is the nicest drive pedal I’ve come across. And trust me I have a wall of od pedals collecting dust. Including an SD-1. I tried all of them. I personally use the Highway 41 and the Statesboro Bluesman which is both from Missing Link. I like the honk of the Bluesman and the lead tone from the Highway 41.

Tube screamer is a mid range booster, fenders tend to lack mids and be more scooped hence the fit.